Objective:This study aims to identify the prevalence of bullying in the workplace and to examine its association with turnover(TO)intention and secondary traumatic stress(STS)among Jordanian nurses employed in Emergen...Objective:This study aims to identify the prevalence of bullying in the workplace and to examine its association with turnover(TO)intention and secondary traumatic stress(STS)among Jordanian nurses employed in Emergency Departments(EDs)and critical care units(CCUs).Nurses employed in the EDs and CCUs are exposed to high levels of bullying behaviors that may contribute to STS,leading to high rates of TO.Methods:A descriptive cross-sectional design was used.A sample of 150 Jordanian nurses working in CCUs and EDs completed the study.Data collection was performed using the Demographical Questionnaire,the Negative Acts Questionnaire-Revised(NAQ-R),ProQOL scale,and TO scale.The IBM SPSS software was used to analyze data.Results:About 10.7%and 89.3%were categorized as“occasionally bullied”and“victims of workplace bullying”subsequently.Workplace bullying was positively associated with TO intention(r=0.46,P<0.001)and STS(r=0.36,P<0.001).TO was positively associated with STS(r=0.36,P<0.001).Bullying was a unique significant predictor of TO intention(t=4.59,B=0.34,P<0.001)and STS(t=4.15,B=0.34,P<0.001).Conclusions:Bullying behavior has negative adversarial effects on TO and the experience of STS.The prevalence of bullying behavior in the EDs and CCUs remains high despite the increasing awareness of its negative impacts.Healthcare organizations should put systems in place to ensure that zero-tolerance policy are monitored in terms of the effectiveness of its implementation.展开更多
This study focuses on the relationship between job stress and intention to leave among obstetric(OB)nurses in the context of China's birth policy adjustment,and provides a scientific basis for policymakers and hea...This study focuses on the relationship between job stress and intention to leave among obstetric(OB)nurses in the context of China's birth policy adjustment,and provides a scientific basis for policymakers and healthcare administrators.This study used a non-experimental descriptive correlation design with a purposive sampling of 230 OB nurses from three tertiary hospitals in Jinan,Shandong Province.Participants were surveyed using three questionnaires and descriptive analysis;ANOVA and correlation analyses were used to analyze the relationship between participants'stressor levels and turnover intention.Pearson's correlation coefficient analysis showed that there was a positive correlation between nurses‘work stressors and turnover intention,with a correlation coefficient of r=0.53,a moderate positive correlation(P<0.001).Based on the survey data from three tertiary hospitals in Shandong Province,the obstetric nurses group has a medium level of work stressors,but a high turnover intention,highlighting the professional identity crisis.展开更多
Background One of the main roles of the intestinal mucosa is to protect against environmental hazards.Supple-mentation of xylo-oligosaccharides(XOS)is known to selectively stimulate the growth of beneficial intestinal...Background One of the main roles of the intestinal mucosa is to protect against environmental hazards.Supple-mentation of xylo-oligosaccharides(XOS)is known to selectively stimulate the growth of beneficial intestinal bacteria and improve gut health and function in chickens.XOS may have an impact on the integrity of the intestinal epithelia where cell turnover is critical to maintain the compatibility between the digestive and barrier functions.The aim of the study was to evaluate the effect of XOS and an arabinoxylan-rich fraction(AXRF)supplementation on gut func-tion and epithelial integrity in broiler chickens.Methods A total of 128 broiler chickens(Ross 308)were assigned into one of two different dietary treatments for a period of 42 d:1)control diet consisting of a corn/soybean meal-based diet;or 2)a control diet supplemented with 0.5%XOS and 1%AXRF.Each treatment was randomly distributed across 8 pens(n=8)with 8 chickens each.Feed intake and body weight were recorded weekly.On d 42,one male chicken per pen was selected based on aver-age weight and euthanized,jejunum samples were collected for proteomics analysis.Results Dietary XOS/AXRF supplementation improved feed efficiency(P<0.05)from d 1 to 42 compared to the con-trol group.Proteomic analysis was used to understand the mechanism of improved efficiency uncovering 346 dif-ferentially abundant proteins(DAP)(Padj<0.00001)in supplemented chickens compared to the non-supplemented group.In the jejunum,the DAP translated into decreased ATP production indicating lower energy expenditure by the tissue(e.g.,inhibition of glycolysis and tricarboxylic acid cycle pathways).In addition,DAP were associated with decreased epithelial cell differentiation,and migration by reducing the actin polymerization pathway.Put-ting the two main pathways together,XOS/AXRF supplementation may decrease around 19%the energy required for the maintenance of the gastrointestinal tract.Conclusions Dietary XOS/AXRF supplementation improved growth efficiency by reducing epithelial cell migration and differentiation(hence,turnover),actin polymerization,and consequently energy requirement for maintenance of the jejunum of broiler chickens.展开更多
Background The study objective was to test the hypothesis that low crude protein(CP)diet with crystalline amino acids(CAA)supplementation improves Lys utilization efficiency for milk production and reduces protein tur...Background The study objective was to test the hypothesis that low crude protein(CP)diet with crystalline amino acids(CAA)supplementation improves Lys utilization efficiency for milk production and reduces protein turnover and muscle protein breakdown.Eighteen lactating multiparous Yorkshire sows were allotted to 1 of 2 isocaloric diets(10.80 MJ/kg net energy):control(CON;19.24%CP)and reduced CP with“optimal”AA profile(OPT;14.00%CP).Sow body weight and backfat were recorded on d 1 and 21 of lactation and piglets were weighed on d 1,14,18,and 21 of lactation.Between d 14 and 18,a subset of 9 sows(CON=4,OPT=5)was infused with a mixed solution of 3-[methyl-2H3]histidine(bolus injection)and[13C]bicarbonate(priming dose)first,then a constant 2-h[13C]bicarbonate infusion followed by a 6-h primed constant[1-13C]lysine infusion.Serial blood and milk sampling were performed to determine plasma and milk Lys enrichment,Lys oxidation rate,whole body protein turnover,and muscle protein breakdown.Results Over the 21-d lactation period,compared to CON,sows fed OPT had greater litter growth rate(P<0.05).Compared to CON,sows fed OPT had greater efficiency of Lys(P<0.05),Lys mammary flux(P<0.01)and whole-body protein turnover efficiency(P<0.05).Compared to CON,sows fed OPT tended to have lower whole body protein breakdown rate(P=0.069).Muscle protein breakdown rate did not differ between OPT and CON(P=0.197).Conclusion Feeding an improved AA balance diet increased efficiency of Lys and reduced whole-body protein turnover and protein breakdown.These results imply that the lower maternal N retention observed in lactating sows fed improved AA balance diets in previous studies may be a result of greater partitioning of AA towards milk rather than greater body protein breakdown.展开更多
Objective:This study aimed to review the relationship between job embeddedness and turnover intentions among nurses and explore the effects of the Job Embeddedness Scale,number of years in the career,education,and mar...Objective:This study aimed to review the relationship between job embeddedness and turnover intentions among nurses and explore the effects of the Job Embeddedness Scale,number of years in the career,education,and marital status on this relationship.Methods:The review was conducted by searching the China Knowledge Resource Integrated Database(CNKI),Weipu Database(CQVIP),China Biology Medicine(CBM),Wanfang Database,PubMed,Web of Science,Embase,CINAHL,and APA-PsycNet for articles on nurses’job embeddedness and turnover from intention up to March 2024.The research quality was evaluated using the Agency for Healthcare Research and Quality(AHRQ)assessment criteria.The review protocol has been registered on PROSPERO[CRD42023483947].Results:The results of this review included 47 studies consisting of 15,742 nurses from seven countries worldwide.A moderate negative correlation was found between job embeddedness and turnover intention(r=0.487).Furthermore,on-the-job embeddedness(r=0.527)was more negatively associated with turnover intention than off-the-job embeddedness(r=0.234).The highest negative correlation was found between sacrifice and turnover intention(r=0.460),while the lowest was for the link(r=0.185).Furthermore,the relationship between job embeddedness and its dimensions with turnover intention was affected by different job embeddedness scales,number of years in the career,education,and marital status(P<0.05).Conclusion:This systematic review and meta-analysis analyzed the relationships between nurses’job embeddedness,dimensions,and turnover intention.Meanwhile,subgroup analysis and meta-regression explored the factors influencing these relationships.It is an important reference for nurse managers to promote nurse retention.展开更多
Beta diversity,the variation of community composition among sites,bridges alpha and gamma diversity and can reveal the mechanisms of community assembly through applying distance-decay models and/or partitioning beta d...Beta diversity,the variation of community composition among sites,bridges alpha and gamma diversity and can reveal the mechanisms of community assembly through applying distance-decay models and/or partitioning beta diversity into turnover and nestedness components from functional and phylogenetic perspectives.Mountains as the most natural experiment system provide good opportunities for exploring beta diversity patterns and the underlying ecological processes.Here,we simultaneously consider distance-decay models and multiple di-mensions of beta diversity to examine spatial variations of bird communities,and to evaluate the relative importance of niche-based and neutral community assembly mechanisms along a 3600-m elevational gradient in the central Himalayas,China.Our results showed that species turnover dominates taxonomic,functional,and phylogenetic beta diversity.We observed strongest evidence of spatial distance decays in taxonomic similarities of birds,followed by its phylogenetic and functional analogues.Turnover component was highest in taxonomic beta diversity,while nestedness component was highest in functional beta diversity.Further,all correlations of assemblage similarity with climatic distance were higher than that with spatial distances.Standardized values of overall taxonomic,functional,and phylogenetic beta diversity and their turnover components increase with increasing elevational distance,while the standardized values of taxonomic and phylogenetic nestedness decreased with increasing elevational distance.Our results highlighted the niche-based deterministic processes in shaping elevational bird diversity patterns that were determined by the relative roles of decreasing trend of environmental filtering and increasing trend of limiting similarity along elevation distances.展开更多
The impact of sex chromosomes and their turnover in speciation remains a subject of ongoing debate in the field of evolutionary biology.Fishes are the largest group of vertebrates,and they exhibit unparalleled sexual ...The impact of sex chromosomes and their turnover in speciation remains a subject of ongoing debate in the field of evolutionary biology.Fishes are the largest group of vertebrates,and they exhibit unparalleled sexual plasticity,as well as diverse sex-determining(SD)genes,sex chromosomes,and sex-determination mechanisms.This diversity is hypothesized to be associated with the frequent turnover of sex chromosomes in fishes.Although it is evident that amh and amhr2 are repeatedly and independently recruited as SD genes,their relationship with the rapid turnover of sex chromosomes and the biodiversity of fishes remains unknown.We summarize the canonical models of sex chromosome turnover and highlight the vital roles of gene mutation and hybridization with empirical evidence.We revisit Haldane’s rule and the large Xeffect and propose the hypothesis that sex chromosomes accelerate speciation by multiplying genotypes via hybridization.By integrating recent findings on the turnover of SD genes,sex chromosomes,and sexdetermination systems in fish species,this review provides insights into the relationship between sex chromosome evolution and biodiversity in fishes.展开更多
Although heteroatom doping is an effective way to improve the catalytic activity of transition metal phosphides(TMPs),the mechanism of activity enhancement needs to be further refined.To this end,we synthesized a Co-d...Although heteroatom doping is an effective way to improve the catalytic activity of transition metal phosphides(TMPs),the mechanism of activity enhancement needs to be further refined.To this end,we synthesized a Co-doped Ni_(2)P catalyst as a research model and found that the introduction of heterogeneous Co reconstructed the charge distribution around the P site,which effectively enhanced the hydrogen evolution reaction(HER)activity of the pure Ni_(2)P.Based on in-situ Raman real-time monitoring technology,we monitored for the first time that Co doping triggered a switch of the active site(from the original Co-active site to the P-active site),which promoted the adsorption of H_(2)O to enhance the HER activity.The density functional theory(DFT)calculations indicated that the P site of Co-Ni_(2)P expressed the highest activity and the Ni site of pure Ni_(2)P expressed the highest activity,which further confirms the in-situ Raman monitoring results.The active site turnover mechanism discovered in this study will undoubtedly provide more rational and targeted ideas for future catalyst design.展开更多
Vietnam's textile and garment industry has fulfilled its 44-billion-USD export turnover target in 2024,an increase of over 11%compared to 2023,thanks to efforts in market diversification,technological innovation,a...Vietnam's textile and garment industry has fulfilled its 44-billion-USD export turnover target in 2024,an increase of over 11%compared to 2023,thanks to efforts in market diversification,technological innovation,and effectively capitalising on the shift in orders.展开更多
Nurse turnover can negatively impact delivering patient care in the health facilities which will affect the patient’s health and reduce the quality of care. The MOH faces a serious challenge or high nursing staff tur...Nurse turnover can negatively impact delivering patient care in the health facilities which will affect the patient’s health and reduce the quality of care. The MOH faces a serious challenge or high nursing staff turnover and the intention to leave the workforce. <strong>Aim:</strong> To explore one of the significant human recourse problems in the MOH and affecting the healthcare system, which is, factors affecting nurses’ turnover in governmental hospitals using Alhassa governmental hospitals as a case study.<strong> Method:</strong> A quantitative research method used to explore the factors affecting nurses’ turnover in the governmental hospitals in Alhassa. <strong>Result:</strong> According to the study finding, management style was a factor more likely to indicate nurses’ turnover. It defines the impact of management style and works environment on nurses’ and clients’ systems. Individual factors were the second influence on their turnover. The balance between nurses’ work and their family need was the first issue that had affected their work. Organization factors are also an influence on the nurses’ turnover in Alhassa region. <strong>Conclusion: </strong>Nurses’ turnover is a significant issue in a human resource in MOH. This study first applied in Alhassa region that highlighted the factors that affect nurses’ turnover. Nurses’ turnover is a continuous problem that occurs in the health facilities related to management method causes, personal causes or organizational causes. Management style was the most influences on nurses’ turnover in this study changing or modifying management style that can intent nurses to continue their work in the hospital in Alhassa region.展开更多
Profitability ratios are a group of financial ratios that indicate how much profit a business is earning within a certain context, while asset utilization ratios indicate how efficient a business is in operating its a...Profitability ratios are a group of financial ratios that indicate how much profit a business is earning within a certain context, while asset utilization ratios indicate how efficient a business is in operating its assets to generate cash. The difference between profitability ratios and turnover ratios is the fact that turnovers are more specific. While profitability ratios measure overall performance in terms of profits, asset utilization ratios focus on specific measurements within the business） We conduct this study to verify the impact of turnover ratios on Jordanian services sectors＇ performance during the period from 2009 to 2012. The study showed that there is no significant impact of turnover ratios on Jordanian services sectors＇ profitability, and by testing the main and sub hypotheses, the study revealed that there is no significant impact of turnover ratios on Jordanian services sectors＇ return on assets （ROA）, there is no significant impact of working capital turnover on Jordanian services sectors＇ ROA, there is no significant impact of total asset turnover on Jordanian services sectors＇ ROA, and there is no significant impact of fixed asset turnover on Jordanian services sectors＇ ROA. Also, the study showed that there is no significant impact of turnover ratios on Jordanian services sectors＇ return on equity （ROE）, there is no significant impact of working capital turnover on Jordanian services sectors＇ ROE, there is no significant impact of total asset turnover on Jordanian services sectors＇ ROE, and there is no significant impact of fixed asset turnover on Jordanian services sectors＇ ROE. Moreover, the study concluded that the educational services sector has the lowest working capital turnover and healthcare services sector has the highest. In addition, we find that the hotels and tourism sector has the lowest total asset turnover ratio, while the utilities and energy sector has the highest and that the hotels and tourism sector has the lowest fixed asset turnover, while the utilities and energy sector has the highest. The transportation sector has the lowest ROA and technology and communication sector has the highest. Finally, we find that transportation sector has the lowest ROE and the technology and communication sector has the highest.展开更多
Background:Nurses'turnover has been a major concern globally,which is strongly influenced by nurses'intent to leave.However,only a few large sample studies on the predictive factors associated with nurses'...Background:Nurses'turnover has been a major concern globally,which is strongly influenced by nurses'intent to leave.However,only a few large sample studies on the predictive factors associated with nurses'turnover intention were conducted in Jiangsu Province.This study mainly aims to examine the level and factors that influence nurses to leave their work in Jiangsu Province of Eastern China.Methods:A cross-sectional survey of 1978 nurses was conducted at 48 hospitals in 14 key cities throughout Jiangsu Province.The turnover intention in nurses was measured by the scale of intent to leave the profession.The work environment of nurses was measured by the Chinese version of the Practice Environment Scale.A multiple linear regression model was applied to analyse the factors associated with turnover intention.Results:The resignation rate of nurses in the hospitals of Jiangsu Province ranged from 0.64%to 12.71%in 2016.The mean scores were 15.50±3.44 for turnover intention,and 3.06±0.51 for work environment.Involvement in hospital affairs,resource adequacy,age,professional title,year(s)working,employment type and education level were the predictors of nurse intent to leave(P<0.05).Conclusion:The work environment of nurses in hospitals must be improved in staffing and resource and nurses'involvement in hospital affairs.The current study corroborates that nurses have high turnover intention.Thus,effective measures are needed to improve nurse accomplishment,professional status,participation in hospital affairs and career planning to reduce their turnover intention.展开更多
Decomposition experiments of 14C-labelled sickle alfalfa in chao soils of different texture and these soils after removal of CaCO3 were carried out under field and laboratory conditions respectively. The amount of res...Decomposition experiments of 14C-labelled sickle alfalfa in chao soils of different texture and these soils after removal of CaCO3 were carried out under field and laboratory conditions respectively. The amount of residual 14C in, or 14CO2 evolved from, the soils at intervals after the beginning of decomposition were measured and the distribution of native and labelled C between particle size fractions isolated from these soils was edtermined. Results showed that contents of both labelled (14C) and non-labelled (12C) carbon decreased with increasing particle size. The enrichment factor for 14C was higher than that for 12C in the clay fraction, the reverse being true for the silt enrichment factors. The effect of soil texture on the decomposition of plant material could not be observed in chao soils when the clay content was lower than 270g kg-1, while it became obvious once CaCO3 was removed from these soils. The decomposition rate of plant material in the soil from which the native CaCO3 was removed was correlated significantly to both the clay content of the soil and the application rate of CaCO3. A preliminary correction equation describing the effect of clay and CaCO3 on the decomposition of organic material in chao soil was derived from the results obtained.展开更多
Objective:The paper aimed to explore the impact of work support and potential for career advancement on the nurse turnover intention in order to find an effective approach to curb high turnover.Methods:A cross-section...Objective:The paper aimed to explore the impact of work support and potential for career advancement on the nurse turnover intention in order to find an effective approach to curb high turnover.Methods:A cross-sectional survey of 526 nurses from eight teaching hospitals in Tianjin,China,was conducted to test the hypothesized multilevel model.The organizational career growth scale,work support scale,and the nurse turnover intention scale were used to measure the effect of organizational career growth and work support on nurse turnover intention.Finally,SPSS 17.0 and AMOS 17.0 software were used to analyse the relationship of these variables.Results:The score of the three scales nurse turnover,organizational career growth,and work support were 1.98±0.60,2.40±0.50,and 4.06±0.98,respectively.The total and direct effects of work support on turnover intention were0.361(p<0.01)and0.147(p<0.01),respectively.The indirect effect was0.169 with a 95%bootstrap confidence interval of0.257 to0.102.Conclusion:The study showed a lack of work support negatively and directly associated with nurse turnover intention.Additional opportunities for career growth within the organization may strengthen the effect of work support and consequently increase the retention of qualified nursing staff.展开更多
Substantial evidence exists that in addition to the well-known complications of diabetes, increased fracture risk is an important morbidity. This risk is probably due to altered bone properties in diabetes. Circulatin...Substantial evidence exists that in addition to the well-known complications of diabetes, increased fracture risk is an important morbidity. This risk is probably due to altered bone properties in diabetes. Circulating biochemical markers of bone turnover have been found to be decreased in type 2 diabetes （T2D） and may be predictive of fractures independently of bone mineral density （BMD）. Serum sclerostin levels have been found to be increased in T2D and appear to be predictive of fracture risk independent of BMD. Bone imaging technologies, including trabecular bone score （TBS） and quantitative CT testing have revealed differences in diabetic bone as compared to non-diabetic individuals. Specifically, high resolution peripheral quantitative CT （HRpQCT） imaging has demonstrated increased cortical porosity in diabetic postmenopausal women. Other factors such as bone marrow fat saturation and advanced glycation endproduct （AGE） accumulation might also relate to bone cell function and fracture risk in diabetes. These data have increased our understanding of how T2D adversely impacts both bone metabolism and fracture risk.展开更多
Background:Old-growth forests are irreplaceable with respect to climate change mitigation and have considerable carbon(C)sink potential in soils.However,the relationship between the soil organic carbon(SOC)turnover ra...Background:Old-growth forests are irreplaceable with respect to climate change mitigation and have considerable carbon(C)sink potential in soils.However,the relationship between the soil organic carbon(SOC)turnover rate and forest development is poorly understood,which hinders our ability to assess the C sequestration capacity of soil in old-growth forests.Methods:In this study,we evaluated the SOC turnover rate by calculating the isotopic enrichment factor β(defined as the slope of the regression between ^(13)C natural abundance and log-transformed C concentrations)along 0-30 cm soil profiles in three successional forests in subtropical China.A lower β(steeper slope)is associated with a higher turnover rate.The three forests were a 60-year-old P.massoniana forest(PF),a 100-year-old coniferous and broadleaved mixed forest(MF),and a 400-year-old monsoon evergreen broadleaved forest(BF).We also analyzed the soil physicochemical properties in these forests to examine the dynamics of SOC turnover during forest succession and the main regulators.Results:The β value for the upper 30-cm soils in the BF was significantly(p<0.05)higher than that in the PF,in addition to the SOC stock,although there were nonsignificant differences between the BF and MF.The β value was significantly(p<0.05)positively correlated with the soil recalcitrance index,total nitrogen,and available nitrogen contents but was significantly(p<0.01)negatively correlated with soil pH.Conclusions:Our results demonstrate that SOC has lower turnover rates in old-growth forests,accompanied by higher soil chemical recalcitrance,nitrogen status,and lower soil pH.This finding helps to elucidate the mechanism underlying C sequestration in old-growth forest soils,and emphasizes the important value of old-growth forests among global C sinks.展开更多
China's forests cover 208.3 million ha and span a wide range of climates and a large variety of forest types, including tropical, temperate, and boreal forests. However, the variation patterns of fine root (< 2...China's forests cover 208.3 million ha and span a wide range of climates and a large variety of forest types, including tropical, temperate, and boreal forests. However, the variation patterns of fine root (< 2 mm in diameter) biomass, production, and turnover from the south to the north are unclear. This study summarizes fine root biomass (FRB), production (FRP) and turnover rate (FRT) in China's forests as reported by 140 case studies published from 1983 to 2014. The results showed that the mean values of FRB, FRP and FRT in China's forests were 278 g m(-2), 366 g m(-2) a(-1), and 1.19 a(-1), respectively. Compared with other studies at the regional or global scales, FRB in China's forests was lower, FRP was similar to estimates at the global scale, but FRT was much higher. FRB, FRP, and FRT in China's forests increased with increasing mean annual precipitation (MAP), indicating that fine root variables were likely related to MAP, rather than mean annual temperature or latitude. This is possibly due to the small variation in temperature but greater variation in precipitation during the growing season. These findings suggest that spatiotemporal variation in precipitation has a more profound impact on fine root dynamics in China's forests, and this will impact carbon and nutrient cycles driven by root turnover in the future.展开更多
Characteristics and tidal flat trends of soil organic matter （SOM） turnover were studied for the Chongmingdongtan Salt Marsh in the Yangtze River estuary, based on analyses of stable carbon isotope composition （δ^...Characteristics and tidal flat trends of soil organic matter （SOM） turnover were studied for the Chongmingdongtan Salt Marsh in the Yangtze River estuary, based on analyses of stable carbon isotope composition （δ^13C）, grain sizes and contents of particulate organic carbon （POC）, total nitrogen （TN） and inorganic carbon （TIC） for three cores excavated from high tidal flat, middle tidal flat and bare flat. Results demonstrate that correlations between soil POC contents and δ^13C values of the salt marsh cores were similar to those between soil organic carbon （SOC） contents and δ^13C values of the upper soil layers of mountainous soil profiles with different altitudes. SOM of salt marsh was generally younger than 100 years, and originated mainly from topsoil erosions in catchments of the Yangtze River. Correlations of TN content with C/N ratio, POC content with TIC content and POC content with δ^13C values for the cores suggest that turnover degrees of SOM from the salt marsh are overall low, and trends of SOM turnover are clear from the bare flat to the high tidal flat. Bare flat samples show characteristics of original sediments, with minor SOM turnover. Turnover processes of SOM have occurred and are discernable in the high and middle tidal flats, and the mixing degrees of SOM compartments with different turnover rates increase with evolution of the muddy tidal flat. The exclusive strata structure of alternate muddy laminae and silty laminae originated from dynamic depositional processes on muddy tidal flat was a great obstacle to vertical migration of dissolved materials, and SOM turnover was then constrained. The muddy tidal flat processes exerted direct influences on sequestration and turnover of SOM in the salt marsh, and had great constraints on the spatial and temporal characteristics of SOM turnover of the Chongmingdongtan Salt Marsh in the Yangtze River estuary.展开更多
Objective: This study aims to determine the mediating effects of psychological empowerment on abusive supervision and turnover intention as perceived by nurses to provide information to change the status of nurse turn...Objective: This study aims to determine the mediating effects of psychological empowerment on abusive supervision and turnover intention as perceived by nurses to provide information to change the status of nurse turnover.Methods: A cross-sectional survey (a questionnaire examining perceptions of abusive supervision,measurement of psychological empowerment,and questionnaire for turnover intention) was used to collect data.A total of 1127 clinical nurses,who were recruited through convenience sampling,participated in the survey.Results: Nurses' average perceived abusive supervision,psychological empowerment,and turnover intention scores were 1.62 ± 0.95,3.24 ± 0.83,and 14.17 ± 3.78,respectively.Psychological empowerment was found to mediate the relationship between abusive supervision and turnover intention (P< 0.01).Turnover intention tends to be stronger and psychological empowerment reduced when nurse managers adopt an abusive leadership style.Conclusions: Nurses' psychological empowerment is an intermediary variable that predicts the relationship between abusive supervision and turnover intention.Nurse managers should manage abusive supervision to increase nurses' psychological empowerment and decrease turnover intention.展开更多
AIM： To investigate the association between serum insulin-like growth factor 1 （IGF-1）, osteocalcin, and parathyroid hormone （PTH） levels with the etiology and clinical condition of patients with chronic liver di...AIM： To investigate the association between serum insulin-like growth factor 1 （IGF-1）, osteocalcin, and parathyroid hormone （PTH） levels with the etiology and clinical condition of patients with chronic liver disease. METHODS： Eighty children with hepatocellular damage were divided into 3 groups according to the etiology of disease infection： bilharziasis （9 patients）, hepatitis B virus （HBV, 12 patients） and hepatitis C virus （HCV, 29 patients）. The Child score index was found as A in 24 patients, B in 22 patients, C in 4 patients. Thirty healthy children served as control group.HBsAg, HBcAbIgM, HBcAbIgG, and anti-HCV were detected using ELISA technique. HCV-RNA was measured by reverse transcription polymerase chain reaction （RT-PCR）. Antibllharzial antibodies were detected by indirect haemagglutination test. Liver function tests were performed using autoanalyser. Serum IGF-1, osteocalcin and PTH levels were measured by ELISA technique. Abdominal ultrasonography was also conducted. RESULTS： Serum IGF-1 level was significantly lower in all patient groups with liver diseases, while serum osteocalcin and PTH levels were significantly elevated in patients with HBV and HCV infections compared with the control group. Serum osteocalcin and PTH concentrations were measured with the severity of liver disease from Child A to C. Child A patients unexpectedly showed significantly reduced IGF-1 levels in comparison to patients staged as Child B or C. Serum osteocalcin level was negatively correlated with albumin （14.7 ± 0.54 vs 3.6 ± 0.10, P 〈 0.05）, while that for PTH was positively correlated with total protein （70.1 ± 2.17 vs 6.7 ± 0.10, P 〈 0.05） in patients with HCV infection.展开更多
文摘Objective:This study aims to identify the prevalence of bullying in the workplace and to examine its association with turnover(TO)intention and secondary traumatic stress(STS)among Jordanian nurses employed in Emergency Departments(EDs)and critical care units(CCUs).Nurses employed in the EDs and CCUs are exposed to high levels of bullying behaviors that may contribute to STS,leading to high rates of TO.Methods:A descriptive cross-sectional design was used.A sample of 150 Jordanian nurses working in CCUs and EDs completed the study.Data collection was performed using the Demographical Questionnaire,the Negative Acts Questionnaire-Revised(NAQ-R),ProQOL scale,and TO scale.The IBM SPSS software was used to analyze data.Results:About 10.7%and 89.3%were categorized as“occasionally bullied”and“victims of workplace bullying”subsequently.Workplace bullying was positively associated with TO intention(r=0.46,P<0.001)and STS(r=0.36,P<0.001).TO was positively associated with STS(r=0.36,P<0.001).Bullying was a unique significant predictor of TO intention(t=4.59,B=0.34,P<0.001)and STS(t=4.15,B=0.34,P<0.001).Conclusions:Bullying behavior has negative adversarial effects on TO and the experience of STS.The prevalence of bullying behavior in the EDs and CCUs remains high despite the increasing awareness of its negative impacts.Healthcare organizations should put systems in place to ensure that zero-tolerance policy are monitored in terms of the effectiveness of its implementation.
文摘This study focuses on the relationship between job stress and intention to leave among obstetric(OB)nurses in the context of China's birth policy adjustment,and provides a scientific basis for policymakers and healthcare administrators.This study used a non-experimental descriptive correlation design with a purposive sampling of 230 OB nurses from three tertiary hospitals in Jinan,Shandong Province.Participants were surveyed using three questionnaires and descriptive analysis;ANOVA and correlation analyses were used to analyze the relationship between participants'stressor levels and turnover intention.Pearson's correlation coefficient analysis showed that there was a positive correlation between nurses‘work stressors and turnover intention,with a correlation coefficient of r=0.53,a moderate positive correlation(P<0.001).Based on the survey data from three tertiary hospitals in Shandong Province,the obstetric nurses group has a medium level of work stressors,but a high turnover intention,highlighting the professional identity crisis.
文摘Background One of the main roles of the intestinal mucosa is to protect against environmental hazards.Supple-mentation of xylo-oligosaccharides(XOS)is known to selectively stimulate the growth of beneficial intestinal bacteria and improve gut health and function in chickens.XOS may have an impact on the integrity of the intestinal epithelia where cell turnover is critical to maintain the compatibility between the digestive and barrier functions.The aim of the study was to evaluate the effect of XOS and an arabinoxylan-rich fraction(AXRF)supplementation on gut func-tion and epithelial integrity in broiler chickens.Methods A total of 128 broiler chickens(Ross 308)were assigned into one of two different dietary treatments for a period of 42 d:1)control diet consisting of a corn/soybean meal-based diet;or 2)a control diet supplemented with 0.5%XOS and 1%AXRF.Each treatment was randomly distributed across 8 pens(n=8)with 8 chickens each.Feed intake and body weight were recorded weekly.On d 42,one male chicken per pen was selected based on aver-age weight and euthanized,jejunum samples were collected for proteomics analysis.Results Dietary XOS/AXRF supplementation improved feed efficiency(P<0.05)from d 1 to 42 compared to the con-trol group.Proteomic analysis was used to understand the mechanism of improved efficiency uncovering 346 dif-ferentially abundant proteins(DAP)(Padj<0.00001)in supplemented chickens compared to the non-supplemented group.In the jejunum,the DAP translated into decreased ATP production indicating lower energy expenditure by the tissue(e.g.,inhibition of glycolysis and tricarboxylic acid cycle pathways).In addition,DAP were associated with decreased epithelial cell differentiation,and migration by reducing the actin polymerization pathway.Put-ting the two main pathways together,XOS/AXRF supplementation may decrease around 19%the energy required for the maintenance of the gastrointestinal tract.Conclusions Dietary XOS/AXRF supplementation improved growth efficiency by reducing epithelial cell migration and differentiation(hence,turnover),actin polymerization,and consequently energy requirement for maintenance of the jejunum of broiler chickens.
基金financially supported by funds from the USDA-NIFA(award number 2014-67015-21832)。
文摘Background The study objective was to test the hypothesis that low crude protein(CP)diet with crystalline amino acids(CAA)supplementation improves Lys utilization efficiency for milk production and reduces protein turnover and muscle protein breakdown.Eighteen lactating multiparous Yorkshire sows were allotted to 1 of 2 isocaloric diets(10.80 MJ/kg net energy):control(CON;19.24%CP)and reduced CP with“optimal”AA profile(OPT;14.00%CP).Sow body weight and backfat were recorded on d 1 and 21 of lactation and piglets were weighed on d 1,14,18,and 21 of lactation.Between d 14 and 18,a subset of 9 sows(CON=4,OPT=5)was infused with a mixed solution of 3-[methyl-2H3]histidine(bolus injection)and[13C]bicarbonate(priming dose)first,then a constant 2-h[13C]bicarbonate infusion followed by a 6-h primed constant[1-13C]lysine infusion.Serial blood and milk sampling were performed to determine plasma and milk Lys enrichment,Lys oxidation rate,whole body protein turnover,and muscle protein breakdown.Results Over the 21-d lactation period,compared to CON,sows fed OPT had greater litter growth rate(P<0.05).Compared to CON,sows fed OPT had greater efficiency of Lys(P<0.05),Lys mammary flux(P<0.01)and whole-body protein turnover efficiency(P<0.05).Compared to CON,sows fed OPT tended to have lower whole body protein breakdown rate(P=0.069).Muscle protein breakdown rate did not differ between OPT and CON(P=0.197).Conclusion Feeding an improved AA balance diet increased efficiency of Lys and reduced whole-body protein turnover and protein breakdown.These results imply that the lower maternal N retention observed in lactating sows fed improved AA balance diets in previous studies may be a result of greater partitioning of AA towards milk rather than greater body protein breakdown.
基金sponsor from the Academic Research Funding of Macao Polytechnic University(Grant number RP/AE-06/2022).
文摘Objective:This study aimed to review the relationship between job embeddedness and turnover intentions among nurses and explore the effects of the Job Embeddedness Scale,number of years in the career,education,and marital status on this relationship.Methods:The review was conducted by searching the China Knowledge Resource Integrated Database(CNKI),Weipu Database(CQVIP),China Biology Medicine(CBM),Wanfang Database,PubMed,Web of Science,Embase,CINAHL,and APA-PsycNet for articles on nurses’job embeddedness and turnover from intention up to March 2024.The research quality was evaluated using the Agency for Healthcare Research and Quality(AHRQ)assessment criteria.The review protocol has been registered on PROSPERO[CRD42023483947].Results:The results of this review included 47 studies consisting of 15,742 nurses from seven countries worldwide.A moderate negative correlation was found between job embeddedness and turnover intention(r=0.487).Furthermore,on-the-job embeddedness(r=0.527)was more negatively associated with turnover intention than off-the-job embeddedness(r=0.234).The highest negative correlation was found between sacrifice and turnover intention(r=0.460),while the lowest was for the link(r=0.185).Furthermore,the relationship between job embeddedness and its dimensions with turnover intention was affected by different job embeddedness scales,number of years in the career,education,and marital status(P<0.05).Conclusion:This systematic review and meta-analysis analyzed the relationships between nurses’job embeddedness,dimensions,and turnover intention.Meanwhile,subgroup analysis and meta-regression explored the factors influencing these relationships.It is an important reference for nurse managers to promote nurse retention.
基金supported by the Key R&D Program of Tibet Auton-omous Region(XZ202301ZY0019G)Project for the Local Development of Science and Technology by the Central Government(XZ202301YD0007C)the National Natural Science Foundation of China(No.31400361).
文摘Beta diversity,the variation of community composition among sites,bridges alpha and gamma diversity and can reveal the mechanisms of community assembly through applying distance-decay models and/or partitioning beta diversity into turnover and nestedness components from functional and phylogenetic perspectives.Mountains as the most natural experiment system provide good opportunities for exploring beta diversity patterns and the underlying ecological processes.Here,we simultaneously consider distance-decay models and multiple di-mensions of beta diversity to examine spatial variations of bird communities,and to evaluate the relative importance of niche-based and neutral community assembly mechanisms along a 3600-m elevational gradient in the central Himalayas,China.Our results showed that species turnover dominates taxonomic,functional,and phylogenetic beta diversity.We observed strongest evidence of spatial distance decays in taxonomic similarities of birds,followed by its phylogenetic and functional analogues.Turnover component was highest in taxonomic beta diversity,while nestedness component was highest in functional beta diversity.Further,all correlations of assemblage similarity with climatic distance were higher than that with spatial distances.Standardized values of overall taxonomic,functional,and phylogenetic beta diversity and their turnover components increase with increasing elevational distance,while the standardized values of taxonomic and phylogenetic nestedness decreased with increasing elevational distance.Our results highlighted the niche-based deterministic processes in shaping elevational bird diversity patterns that were determined by the relative roles of decreasing trend of environmental filtering and increasing trend of limiting similarity along elevation distances.
基金supported by the National Natural Science Foundation of China(31861123001,31630082,and 32172953)National Key Research and Development Program of China(2022YFD1201600)+2 种基金Chongqing Fishery Technology Innovation Union(CQFTIU2024-08)the Science Foundation of School of Life Sciences SWU(20232005276101)the US National Science Foundation(DEB#1830753)。
文摘The impact of sex chromosomes and their turnover in speciation remains a subject of ongoing debate in the field of evolutionary biology.Fishes are the largest group of vertebrates,and they exhibit unparalleled sexual plasticity,as well as diverse sex-determining(SD)genes,sex chromosomes,and sex-determination mechanisms.This diversity is hypothesized to be associated with the frequent turnover of sex chromosomes in fishes.Although it is evident that amh and amhr2 are repeatedly and independently recruited as SD genes,their relationship with the rapid turnover of sex chromosomes and the biodiversity of fishes remains unknown.We summarize the canonical models of sex chromosome turnover and highlight the vital roles of gene mutation and hybridization with empirical evidence.We revisit Haldane’s rule and the large Xeffect and propose the hypothesis that sex chromosomes accelerate speciation by multiplying genotypes via hybridization.By integrating recent findings on the turnover of SD genes,sex chromosomes,and sexdetermination systems in fish species,this review provides insights into the relationship between sex chromosome evolution and biodiversity in fishes.
基金financial support from the National Natural Science Foundation of China(No.52302098,52336003,52176076,51676103)China Postdoctoral Science Foundation(2023M731855)+3 种基金Taishan Scholar Project of Shandong Province(China)(No.ts20190937)Natural Science Foundation of Shandong Province(China)(No.ZR2023QE344,ZR2021LFG003)Qingdao Postdoctoral Science Foundation(No.QDBSH20220201021,QDBSH20220202084)The Youth Innovation Project for Universities of Shandong Province(2023KJ102)。
文摘Although heteroatom doping is an effective way to improve the catalytic activity of transition metal phosphides(TMPs),the mechanism of activity enhancement needs to be further refined.To this end,we synthesized a Co-doped Ni_(2)P catalyst as a research model and found that the introduction of heterogeneous Co reconstructed the charge distribution around the P site,which effectively enhanced the hydrogen evolution reaction(HER)activity of the pure Ni_(2)P.Based on in-situ Raman real-time monitoring technology,we monitored for the first time that Co doping triggered a switch of the active site(from the original Co-active site to the P-active site),which promoted the adsorption of H_(2)O to enhance the HER activity.The density functional theory(DFT)calculations indicated that the P site of Co-Ni_(2)P expressed the highest activity and the Ni site of pure Ni_(2)P expressed the highest activity,which further confirms the in-situ Raman monitoring results.The active site turnover mechanism discovered in this study will undoubtedly provide more rational and targeted ideas for future catalyst design.
文摘Vietnam's textile and garment industry has fulfilled its 44-billion-USD export turnover target in 2024,an increase of over 11%compared to 2023,thanks to efforts in market diversification,technological innovation,and effectively capitalising on the shift in orders.
文摘Nurse turnover can negatively impact delivering patient care in the health facilities which will affect the patient’s health and reduce the quality of care. The MOH faces a serious challenge or high nursing staff turnover and the intention to leave the workforce. <strong>Aim:</strong> To explore one of the significant human recourse problems in the MOH and affecting the healthcare system, which is, factors affecting nurses’ turnover in governmental hospitals using Alhassa governmental hospitals as a case study.<strong> Method:</strong> A quantitative research method used to explore the factors affecting nurses’ turnover in the governmental hospitals in Alhassa. <strong>Result:</strong> According to the study finding, management style was a factor more likely to indicate nurses’ turnover. It defines the impact of management style and works environment on nurses’ and clients’ systems. Individual factors were the second influence on their turnover. The balance between nurses’ work and their family need was the first issue that had affected their work. Organization factors are also an influence on the nurses’ turnover in Alhassa region. <strong>Conclusion: </strong>Nurses’ turnover is a significant issue in a human resource in MOH. This study first applied in Alhassa region that highlighted the factors that affect nurses’ turnover. Nurses’ turnover is a continuous problem that occurs in the health facilities related to management method causes, personal causes or organizational causes. Management style was the most influences on nurses’ turnover in this study changing or modifying management style that can intent nurses to continue their work in the hospital in Alhassa region.
文摘Profitability ratios are a group of financial ratios that indicate how much profit a business is earning within a certain context, while asset utilization ratios indicate how efficient a business is in operating its assets to generate cash. The difference between profitability ratios and turnover ratios is the fact that turnovers are more specific. While profitability ratios measure overall performance in terms of profits, asset utilization ratios focus on specific measurements within the business） We conduct this study to verify the impact of turnover ratios on Jordanian services sectors＇ performance during the period from 2009 to 2012. The study showed that there is no significant impact of turnover ratios on Jordanian services sectors＇ profitability, and by testing the main and sub hypotheses, the study revealed that there is no significant impact of turnover ratios on Jordanian services sectors＇ return on assets （ROA）, there is no significant impact of working capital turnover on Jordanian services sectors＇ ROA, there is no significant impact of total asset turnover on Jordanian services sectors＇ ROA, and there is no significant impact of fixed asset turnover on Jordanian services sectors＇ ROA. Also, the study showed that there is no significant impact of turnover ratios on Jordanian services sectors＇ return on equity （ROE）, there is no significant impact of working capital turnover on Jordanian services sectors＇ ROE, there is no significant impact of total asset turnover on Jordanian services sectors＇ ROE, and there is no significant impact of fixed asset turnover on Jordanian services sectors＇ ROE. Moreover, the study concluded that the educational services sector has the lowest working capital turnover and healthcare services sector has the highest. In addition, we find that the hotels and tourism sector has the lowest total asset turnover ratio, while the utilities and energy sector has the highest and that the hotels and tourism sector has the lowest fixed asset turnover, while the utilities and energy sector has the highest. The transportation sector has the lowest ROA and technology and communication sector has the highest. Finally, we find that transportation sector has the lowest ROE and the technology and communication sector has the highest.
基金This study was supported by the Jiangsu Provincial Health and Family Planning Commission(WSGL201605)
文摘Background:Nurses'turnover has been a major concern globally,which is strongly influenced by nurses'intent to leave.However,only a few large sample studies on the predictive factors associated with nurses'turnover intention were conducted in Jiangsu Province.This study mainly aims to examine the level and factors that influence nurses to leave their work in Jiangsu Province of Eastern China.Methods:A cross-sectional survey of 1978 nurses was conducted at 48 hospitals in 14 key cities throughout Jiangsu Province.The turnover intention in nurses was measured by the scale of intent to leave the profession.The work environment of nurses was measured by the Chinese version of the Practice Environment Scale.A multiple linear regression model was applied to analyse the factors associated with turnover intention.Results:The resignation rate of nurses in the hospitals of Jiangsu Province ranged from 0.64%to 12.71%in 2016.The mean scores were 15.50±3.44 for turnover intention,and 3.06±0.51 for work environment.Involvement in hospital affairs,resource adequacy,age,professional title,year(s)working,employment type and education level were the predictors of nurse intent to leave(P<0.05).Conclusion:The work environment of nurses in hospitals must be improved in staffing and resource and nurses'involvement in hospital affairs.The current study corroborates that nurses have high turnover intention.Thus,effective measures are needed to improve nurse accomplishment,professional status,participation in hospital affairs and career planning to reduce their turnover intention.
文摘Decomposition experiments of 14C-labelled sickle alfalfa in chao soils of different texture and these soils after removal of CaCO3 were carried out under field and laboratory conditions respectively. The amount of residual 14C in, or 14CO2 evolved from, the soils at intervals after the beginning of decomposition were measured and the distribution of native and labelled C between particle size fractions isolated from these soils was edtermined. Results showed that contents of both labelled (14C) and non-labelled (12C) carbon decreased with increasing particle size. The enrichment factor for 14C was higher than that for 12C in the clay fraction, the reverse being true for the silt enrichment factors. The effect of soil texture on the decomposition of plant material could not be observed in chao soils when the clay content was lower than 270g kg-1, while it became obvious once CaCO3 was removed from these soils. The decomposition rate of plant material in the soil from which the native CaCO3 was removed was correlated significantly to both the clay content of the soil and the application rate of CaCO3. A preliminary correction equation describing the effect of clay and CaCO3 on the decomposition of organic material in chao soil was derived from the results obtained.
文摘Objective:The paper aimed to explore the impact of work support and potential for career advancement on the nurse turnover intention in order to find an effective approach to curb high turnover.Methods:A cross-sectional survey of 526 nurses from eight teaching hospitals in Tianjin,China,was conducted to test the hypothesized multilevel model.The organizational career growth scale,work support scale,and the nurse turnover intention scale were used to measure the effect of organizational career growth and work support on nurse turnover intention.Finally,SPSS 17.0 and AMOS 17.0 software were used to analyse the relationship of these variables.Results:The score of the three scales nurse turnover,organizational career growth,and work support were 1.98±0.60,2.40±0.50,and 4.06±0.98,respectively.The total and direct effects of work support on turnover intention were0.361(p<0.01)and0.147(p<0.01),respectively.The indirect effect was0.169 with a 95%bootstrap confidence interval of0.257 to0.102.Conclusion:The study showed a lack of work support negatively and directly associated with nurse turnover intention.Additional opportunities for career growth within the organization may strengthen the effect of work support and consequently increase the retention of qualified nursing staff.
文摘Substantial evidence exists that in addition to the well-known complications of diabetes, increased fracture risk is an important morbidity. This risk is probably due to altered bone properties in diabetes. Circulating biochemical markers of bone turnover have been found to be decreased in type 2 diabetes （T2D） and may be predictive of fractures independently of bone mineral density （BMD）. Serum sclerostin levels have been found to be increased in T2D and appear to be predictive of fracture risk independent of BMD. Bone imaging technologies, including trabecular bone score （TBS） and quantitative CT testing have revealed differences in diabetic bone as compared to non-diabetic individuals. Specifically, high resolution peripheral quantitative CT （HRpQCT） imaging has demonstrated increased cortical porosity in diabetic postmenopausal women. Other factors such as bone marrow fat saturation and advanced glycation endproduct （AGE） accumulation might also relate to bone cell function and fracture risk in diabetes. These data have increased our understanding of how T2D adversely impacts both bone metabolism and fracture risk.
基金jointly supported by the China Postdoctoral Science Foundation(No.2020 M682951)the National Natural Science Foundation of China(No.NSFC41773088)the Key Research Program of the Chinese Academy of Sciences(No.QYZDJ-SSW-DQC003).
文摘Background:Old-growth forests are irreplaceable with respect to climate change mitigation and have considerable carbon(C)sink potential in soils.However,the relationship between the soil organic carbon(SOC)turnover rate and forest development is poorly understood,which hinders our ability to assess the C sequestration capacity of soil in old-growth forests.Methods:In this study,we evaluated the SOC turnover rate by calculating the isotopic enrichment factor β(defined as the slope of the regression between ^(13)C natural abundance and log-transformed C concentrations)along 0-30 cm soil profiles in three successional forests in subtropical China.A lower β(steeper slope)is associated with a higher turnover rate.The three forests were a 60-year-old P.massoniana forest(PF),a 100-year-old coniferous and broadleaved mixed forest(MF),and a 400-year-old monsoon evergreen broadleaved forest(BF).We also analyzed the soil physicochemical properties in these forests to examine the dynamics of SOC turnover during forest succession and the main regulators.Results:The β value for the upper 30-cm soils in the BF was significantly(p<0.05)higher than that in the PF,in addition to the SOC stock,although there were nonsignificant differences between the BF and MF.The β value was significantly(p<0.05)positively correlated with the soil recalcitrance index,total nitrogen,and available nitrogen contents but was significantly(p<0.01)negatively correlated with soil pH.Conclusions:Our results demonstrate that SOC has lower turnover rates in old-growth forests,accompanied by higher soil chemical recalcitrance,nitrogen status,and lower soil pH.This finding helps to elucidate the mechanism underlying C sequestration in old-growth forest soils,and emphasizes the important value of old-growth forests among global C sinks.
基金supported by Grants from the National Key Research and Development Program of China(2016YFD06004040604)the Natural Science Foundation of Heilongjiang Province(No.C2016004)
文摘China's forests cover 208.3 million ha and span a wide range of climates and a large variety of forest types, including tropical, temperate, and boreal forests. However, the variation patterns of fine root (< 2 mm in diameter) biomass, production, and turnover from the south to the north are unclear. This study summarizes fine root biomass (FRB), production (FRP) and turnover rate (FRT) in China's forests as reported by 140 case studies published from 1983 to 2014. The results showed that the mean values of FRB, FRP and FRT in China's forests were 278 g m(-2), 366 g m(-2) a(-1), and 1.19 a(-1), respectively. Compared with other studies at the regional or global scales, FRB in China's forests was lower, FRP was similar to estimates at the global scale, but FRT was much higher. FRB, FRP, and FRT in China's forests increased with increasing mean annual precipitation (MAP), indicating that fine root variables were likely related to MAP, rather than mean annual temperature or latitude. This is possibly due to the small variation in temperature but greater variation in precipitation during the growing season. These findings suggest that spatiotemporal variation in precipitation has a more profound impact on fine root dynamics in China's forests, and this will impact carbon and nutrient cycles driven by root turnover in the future.
基金Foundation： National Natural Science foundation of China, No.40202032 National 973 Project, No.2002CB412403 Program for Young Teachers in Universities in Shanghai, No.2000QN 14 Acknowledgments： We are grateful to the members taking part in a field survey supervised by Professor Zhang Jing for their kind helps in sampling the studied cores in this paper. Thanks are also extended to Mr. Wu Runming and Mr. Zhang Guosen for their instructions and helps in laboratory analyses.
文摘Characteristics and tidal flat trends of soil organic matter （SOM） turnover were studied for the Chongmingdongtan Salt Marsh in the Yangtze River estuary, based on analyses of stable carbon isotope composition （δ^13C）, grain sizes and contents of particulate organic carbon （POC）, total nitrogen （TN） and inorganic carbon （TIC） for three cores excavated from high tidal flat, middle tidal flat and bare flat. Results demonstrate that correlations between soil POC contents and δ^13C values of the salt marsh cores were similar to those between soil organic carbon （SOC） contents and δ^13C values of the upper soil layers of mountainous soil profiles with different altitudes. SOM of salt marsh was generally younger than 100 years, and originated mainly from topsoil erosions in catchments of the Yangtze River. Correlations of TN content with C/N ratio, POC content with TIC content and POC content with δ^13C values for the cores suggest that turnover degrees of SOM from the salt marsh are overall low, and trends of SOM turnover are clear from the bare flat to the high tidal flat. Bare flat samples show characteristics of original sediments, with minor SOM turnover. Turnover processes of SOM have occurred and are discernable in the high and middle tidal flats, and the mixing degrees of SOM compartments with different turnover rates increase with evolution of the muddy tidal flat. The exclusive strata structure of alternate muddy laminae and silty laminae originated from dynamic depositional processes on muddy tidal flat was a great obstacle to vertical migration of dissolved materials, and SOM turnover was then constrained. The muddy tidal flat processes exerted direct influences on sequestration and turnover of SOM in the salt marsh, and had great constraints on the spatial and temporal characteristics of SOM turnover of the Chongmingdongtan Salt Marsh in the Yangtze River estuary.
基金This work was supported by the Natural Science Foundation of China(No.71704040)
文摘Objective: This study aims to determine the mediating effects of psychological empowerment on abusive supervision and turnover intention as perceived by nurses to provide information to change the status of nurse turnover.Methods: A cross-sectional survey (a questionnaire examining perceptions of abusive supervision,measurement of psychological empowerment,and questionnaire for turnover intention) was used to collect data.A total of 1127 clinical nurses,who were recruited through convenience sampling,participated in the survey.Results: Nurses' average perceived abusive supervision,psychological empowerment,and turnover intention scores were 1.62 ± 0.95,3.24 ± 0.83,and 14.17 ± 3.78,respectively.Psychological empowerment was found to mediate the relationship between abusive supervision and turnover intention (P< 0.01).Turnover intention tends to be stronger and psychological empowerment reduced when nurse managers adopt an abusive leadership style.Conclusions: Nurses' psychological empowerment is an intermediary variable that predicts the relationship between abusive supervision and turnover intention.Nurse managers should manage abusive supervision to increase nurses' psychological empowerment and decrease turnover intention.
基金Supported by the National Research Centre during the research plan from 2001-2004 by projects 5/4/5 and 5/5/5 in collaboration with National Liver Institute of Menoufyia University
文摘AIM： To investigate the association between serum insulin-like growth factor 1 （IGF-1）, osteocalcin, and parathyroid hormone （PTH） levels with the etiology and clinical condition of patients with chronic liver disease. METHODS： Eighty children with hepatocellular damage were divided into 3 groups according to the etiology of disease infection： bilharziasis （9 patients）, hepatitis B virus （HBV, 12 patients） and hepatitis C virus （HCV, 29 patients）. The Child score index was found as A in 24 patients, B in 22 patients, C in 4 patients. Thirty healthy children served as control group.HBsAg, HBcAbIgM, HBcAbIgG, and anti-HCV were detected using ELISA technique. HCV-RNA was measured by reverse transcription polymerase chain reaction （RT-PCR）. Antibllharzial antibodies were detected by indirect haemagglutination test. Liver function tests were performed using autoanalyser. Serum IGF-1, osteocalcin and PTH levels were measured by ELISA technique. Abdominal ultrasonography was also conducted. RESULTS： Serum IGF-1 level was significantly lower in all patient groups with liver diseases, while serum osteocalcin and PTH levels were significantly elevated in patients with HBV and HCV infections compared with the control group. Serum osteocalcin and PTH concentrations were measured with the severity of liver disease from Child A to C. Child A patients unexpectedly showed significantly reduced IGF-1 levels in comparison to patients staged as Child B or C. Serum osteocalcin level was negatively correlated with albumin （14.7 ± 0.54 vs 3.6 ± 0.10, P 〈 0.05）, while that for PTH was positively correlated with total protein （70.1 ± 2.17 vs 6.7 ± 0.10, P 〈 0.05） in patients with HCV infection.
